v0.11.0

Add MongoDB connector (17) + polish review fixes

- New mongodb connector (group Data, NoSQL, standalone via the mongodb 3.x
  driver): list databases/collections, find (JSON filter), count; insert
  document gated behind Writer; --manifest + --test-connection. Wired into
  workspace, both CI bin-lists, app embed, registry (now 17), site, README,
  JSON-LD. Package is mongodb-connector, binary mongodb.
- Polish review (verdict: ship): removed dead install_hint i18n key (EN+VI);
  strengthened the hero CTA border (hairline to hairline-strong) so it reads
  as clickable.
- 24 E2E green; app compiles with MongoDB embedded.